1. Field of Invention
This invention relates generally to a safety helmet for bicyclists, and more particularly to a safety helmet that is interactive with like helmets, making it possible for a group of bicyclists wearing these helmets to communicate with each other and thereby coordinate their activities.
2. Status of Prior Art
In my above-identified copending patent application, there is disclosed a bicycle having incorporated in its frame a battery power pack for supplying operating power to bicycle accessories, such as head and tail lights. The bicycle power pack is also capable of supplying power to a safety helmet worn by a bicyclist, the helmet being equipped with a radio and safety lights.
Because the power supply for the helmet is external thereto, the helmet is not weighed down by batteries and can be comfortably worn by the bicyclist. And because the safety lights and the radio included in the helmet are without batteries, they are highly compact and add little weight to the helmet.
The safety helmet disclosed in my copending patent application, though protective of a bicyclist's head, does not take into account the fact that bicyclists often travel in groups, very much in the manner of motorcyclists who belong to a motorcycle club. When travelling in a group, bicyclists need to be able to communicate with each other in order to coordinate their activities.
Thus when a group of young bicyclists are travelling together toward a camping site in a state park many miles from their city homes, it is essential, especially in the hours when the bicyclists are travelling on unlighted roads, that the bicyclists keep in touch with each other. The bicyclists in the group usually travel one behind the other on the road with a spacing between successive bicyclists that depends on how fast each bicyclist can pedal. It is important that no bicyclist in the group fall so far behind the others that he becomes separated from the group.
The present practice for coordinating the activities of a group of bicyclists is by hand signals. These leave much to be desired, for some bicyclists in the group may be beyond the range in which these hand signals can be seen. Also the visibility of hand signals depends on ambient light conditions.
Also important to the safety of a bicyclists are safety lights which call attention to the bicycle and the direction in which it is travelling. Bicycles which travel at night are equipped with head and tail lights, one usually being attached to the handle bar and the other to the rear fender. But these lights may escape the attention of driver's in motorized vehicles approaching the front or rear end of the bicycle. Thus a driver in the elevated cab of a large truck is positioned well above the level of a bicycle and may therefore fail to see light rays emanating from safety lights on the bicycle close to the road.
On the other hand, safety light placed on a helmet worn by the bicyclist are at a higher level and therefore are more visible to the drivers of approaching vehicles. But when such lights are produced by incandescent light bulbs, the greater their intensity the more power they require, and if this power is provided by batteries housed in the helmet, the batteries then add excessive weight to the helmet.
In signal light units included in a helmet in accordance with the invention, light flashes are emitted by LED'S. Of prior art interest is the Choi et al. U.S. Pat No. 5,313,187 which discloses superluminescent LED's driven by a low-frequency oscillator to produce light flashes at a frequency of 31/2 pulses a second to serve as a flashing light warning device on a bicycle.